Solar fruit dryer to help the Colombian peace community San José receive fair banana prices

by Julien Wagemann *

During the peace training session of the Global Campus in Tamera, energy technologists and students built the prototype for a solar fruit dryer: With more advanced technology, it will eventually help the residents of the Peace Village of San Jose in Colombia to sell their bananas as a dried fruit to Europe and thus receive a fair price for their main product.


There can never be too many sweet dried bananas. At least this is what the peace community San José de Apartadó thinks. Together with the Tamera energy technologists, they constructed a prototype for a Solar fruit dryer. Not only should it dry bananas, but also cocoa beans and rice should sweat in this solar sauna for food. When dried, the fruit is, in fact, much more durable, without losing too many vitamins and enzymes. From then on, it's only a matter of time before they are enjoyed by European families.

In the Peace Village San José de Apartadó, almost half the banana crop had to be disposed of this year, because whereas the big companies can sell the bananas at a much lower price, fresh organic bananas from the peace community have no chance of being sold for a fair price. The Peace Village therefore sells as many bananas as possible to a fair trade retailer in Bogotá, which produces dried fruits thereof. But on the long way from the Caribbean tropics, some become mushy.


The solution to this would be for the Peace community to have its own dryer. This would have another effect: With the sale of dried banana directly to a European buyer, the peace community would also receive a much better price for their products. It would be a regular income, with which San Jose could finance its schools. Knowing all this, we can tell that a fruit dryer would be a big establishment for the future of the peace village. The best type would be one that needs no electricity, because the farmers want to remain autonomous.

The Solar Dryer that has been built now in Tamera needs no solar panel and can even be manufactured from materials that are found on rubbish dumps: boards, wood, plastic film. It works quite simply: The air is heated by a black foil and directed into a drying cabinet in which the fruit - hanging in the air - are waiting in the dark to get dry.


Such a dryer is of interest not only for Colombia, but it can also help communities in India and Brazil take another step toward autonomy. That´s why the representative of the Barefoot College and the members of "Favela da Paz" from Sao Paulo took part in the building of the dryer.

One does not have to be a professor in energy technology to build such a cabinet dryer. Anyone who ever asssembled an Ikea cabinet can do it.  For both, you need good instructions. That´s why a prototype was built. The model for practice and experimentation has already provided the first tasty, dry prunes, pears, bananas, and tomatoes after only two days. 

Anyone who wants to can upgrade his cabinet dryer with a clay oven in order to be able to dry fruits even at night or during rainy seasons.


The dryer now needs to be adapted to the specific conditions in Colombia: the inventors´ brains are already working at full speed, and energy specialist Juergen Kleinwächter has promising technical suggestions on how, even during moist nights and in the rainy season, large quantities of excellent, durable and healthy dried fruit can be produced.

Meanwhile, the team of the Global Campus is happy about the first simple and very effective cabinet dryer, which is already in use every day.


*Julien Wagemann, 18, an intern in Tamera Press Office

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